[Haskell-cafe] Re: Composing monads

Hitesh hitesh.jasani at gmail.com
Fri Nov 23 16:20:19 EST 2007


> main :: IO ()
> main = mapM_ ((putStrLn "") >*> putStrLn) $
>            map show [1,2,3]
> 

A couple other ways to do this code.

Without monad combinators

main = mapM_ putStrLn . ("":) . intersperse "" . map show $ [1..3]


With your combinator, but collapsing it so we don't map over the
collection twice.

main = mapM_ ((putStrLn "") >*> print) $ [1..3]

- Hitesh




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